Are the thoughts and obsessions that cast doubt on the existence of God and faith, which were caused by watching a program on atheism, along with a constant fear of falling into disbelief and atheism—are these considered disobedience to God and a departure from religion, despite belief in God and fear of Him?

The cure for obsessive thoughts is the remembrance of Allah and to suppress them, without giving in to them. The soul's tranquility through the remembrance of Allah is a sign of faith, not disbelief, as Allah Almighty said: "Those who have believed and whose hearts are assured by the remembrance of Allah. Unquestionably, by the remembrance of Allah hearts are assured." What a person finds within himself of obsessive thoughts and is unable to speak of is pure faith, as stated in Sahih (definition) Muslim. This is from the schemes of Satan and does not harm the one who experiences it.